Ops 102: Class 03

This topic relates to what I am studying, because in this module we are finding out how the computer boots up. This includes how the computer knows what the settings are (date, time, system hardware settings, user preferences, and password for your computer) even after it has been removed from power.

Things I want to know more about:

• What External Peripheral Devices are, how many there can be, and what do they do? What are Device Drivers? Does the CMOS Battery ever die, does it need to be replaced ever, under what circumstances will the CMOS Battery need to be replaced, and what exactly is the process for replacing the battery? Finally, I would like the instructors to walk me through the entire boot up process step-by-step while explaining what each element in the process is doing.

What is the BIOS?

• "The BIOS (ROMBIOS) is a system utility software that is placed in a ROM chip (Read only) on the computer system motherboard as a firmware" (Learn Computer Science). BIOS is also called basic input output system, and loads the operating system into the main system memory RAM. Use analogies from your previous background to explain what happens during the booting process?
• To me it is like my memory when I wake up in the morning. My brain is the CPU and my brain is attempting to extract yesterday's memories (BIOS), and as I sit up then finally stand up my memory is fully restored. My background is in Gas Turbine Engines, so the equivalent would have to be similar to computers. When I push the start button for an LM2500 engine, the IIEC (also the brain of the engine and its components) will remember if the engine had any faults or irregularities before it was last shut off, and if not then it will utilize/remember its known parameters and cycles for start-up (I don't know what would be similar to BIOS in the IIEC because I never had the opportunity to take it apart since it was not a part of my job description). After the engine reaches idle speed, all start-up parameters and safeties are no longer in place (BIOS) because it handed the job off to running parameters and safeties (the main RAM). What is the “Power On Self Test”?
• The Power On Self Test is what the system power supply unit does when the computer is turned on. This test "checks the computer systems internal hardware components for compatibility, connection and ensures that no errors exist before loading the operating system" (Learn Computer Science). This POST is checking that the power supplied is sufficient enough, then checks the externals (i.e. mouse, monitor, keyboard, RAM), after the power supply check it sends adequate power signal to the CPU. What is the CMOS?
• The CMOS (Complementary Metal Oxide Semiconductor) "is a small battery powered RAM memory which retains the user settings and data required during the booting process" (Learn Computer Science). "The CMOS is type of technology used to produce integrated circuits (IC Chips)" (Learn Computer Science). The CMOS chip stores critical data during the booting process. CMOS and BIOS work together during start-up. Additionally, the CMOS can be referred to as a Real-Time Clock (RTC). What is the CMOS battery?
• The CMOS battery is what allows the CMOS to be a Non-Volatile RAM (NVRAM) or CMOS RAM, because when the computer is turned off or unplugged it powers the CMOS chip. This allows the CMOS to retain stored data (BIOS settings) when the computer has no power. "The CMOS is a battery powered semiconductor chip (memory) inside computer that stores the information needed during the computer booting process" (Learn Computer Science).

References

Learn Computer Science. (n.d.). BIOS and CMOS. LearnComputerScience.com